I had a lot of fun creating this and utilizing the Big.js library for helping handle the decimal points and arithmetic logic. I tried to get this as close as possible to the exiting iOS Calculator, even by making the button colors fade when pressed. Enjoy!
Responsive to a variety of screen sizes! My favorite is using it like it's the size on the iPhone 8 Plus (414 x 736). You should be able to size it to whatever size you are comfortable with, but not any smaller than an average size smartphone.
For this application I built this entirely with the following:
Copyright (c) 2019 Kaitlyn Flynn